1. Technical Field of the Invention
This invention relates to an improved method and system for use with earth retaining structures, and more particularly, an improved retaining wall link and loop combination for attaching a welded wire gridwork panel to the face panels of the wall. This utility patent application claims the priority date of Provisional Patent Application Ser. No. 60/077,724 filed Mar. 12, 1998 and is hereby incorporated by reference.
2. Description of Related Art
A retaining wall is used for retaining earth and/or other backfill material placed behind the wall. Elongated support structures normally extend from various locations on the back surface of the wall into the backfill material. The support members are embedded into the backfill material and prevent the wall from buckling outwardly.
The retaining wall may be constructed of an unbroken stretch of concrete which usually is poured on site. Alternatively, the wall may be constructed of a plurality of modular concrete blocks which are assembled on site. Generally, modular blocks are less expensive to construct and assemble than a large, single piece of concrete because of the difficulty in transporting and pouring large amounts of concrete. Additionally, the amount of time required for assembling the modular blocks is generally less than that required for pouring concrete walls.
A major difficulty is encountered in attaching the support members to the modular blocks. Several methods and apparatus have been provided in the past for attaching the support members to the modular blocks. However, installation of these prior art devices onto retaining walls is often tedious and time consuming. In addition, difficulties are encountered in providing a strong enough connecting device connecting the retaining wall with the support members, in order to support the heavy forces placed on the retaining wall. A system and method are needed for attaching support members to a modular block which are easy to install, and provides the requisite strength necessary to reinforce a retaining wall.
Although there are no known prior art teachings of a solution to the aforementioned deficiency and shortcoming such as that disclosed herein, prior art references that discuss subject matter that bears some relation to matters discussed herein are U.S. Pat. No. 4,324,508 to Hilfiker et al. (Hilfiker I), U.S. Pat. No. 4,449,857 to Davis (Davis I), U.S. Pat. No. 4,725,170 to Davis (Davis II), and U.S. Pat. No. 4,929,125 to Hilfiker (Hilfiker II).
Hilfiker I discloses welded wire grid work mats which are positioned within an earthen formation. The mats are secured to precast elongated panels disposed at the face of the earthen formation. The mats serve as anchors for the panels, as well as reinforcing means for the formation. Plural connections secure the mats along the length of the panels. However, the mats may slip within the earthen formation, and Hilfiker I does not teach or suggest utilizing any method to prevent slippage of the grid work mats.
Davis I discloses a connection system for connecting an upright soil retaining wall formed of modular facing panels with a number of soil reinforcement panels formed of parallel wires. The parallel wires terminate in enlarged bulbous portions at one end and are interconnected by perpendicular crossbars. The mesh units are connected in tiers to the retaining wall and rest in the soil behind the wall. The connection is made by a female member embedded into the back side of the panel with internal threads, into a male member which is threadedly received with an internal bore of a suitable size to pass the wires but not the bulbous portions which bear against the forward end of the bolts. With the wires seated within a corresponding male member, the facing panels and mesh units are connected by screwing the male member into the female member. Davis I suffers from the disadvantage of a complex and time consuming process of threading the male members into female members in order to connect the wire mesh reinforcement units to the retaining wall.
Davis II discloses a soil retaining system which includes an upright soil retaining wall of modular facing panels and a number of horizontal wire mesh reinforcement units. Each unit includes spaced parallel wires ending in hole forming loops and interconnected by perpendicular crossbars. The mesh units are connected in tiers to the retaining wall and rest in the soil behind the wall. The connection of each wire in a mesh unit is made by a clevis member embedded into the back side of the panel and a bolt and nut assembly or an elongated pin member for attaching the wires and the clevis. However, Davis II is a more complex and expensive system than the present invention.
Hilfiker II discloses a reinforced soil embankment having precast face panels with cantilevered sections extending into the embankment to support the panels in an upright condition. Soil reinforcing elements are secured to the panels to reinforce the embankment and secure the face panels in place. Connectors are provided for securing and reinforcing the elements to the panels. Loops, formed on the ends of the elements, are extended through eyes on the panels formed by wire segment having legs which extend into the face panels. However, Hilfiker II requires very precise alignment of the wire segments embedded in the face panels with the soil reinforcing elements. Thus, Hilfiker II provides a very inflexible method of attaching soil reinforcing elements to a retaining wall.
Review of each of the foregoing references reveals no disclosure or suggestion of a system or method as that described and claimed herein. Thus, it would be a distinct advantage to have a system and method which inexpensively and simply attaches supporting elements to retaining walls. It is an object of the present invention to provide such a system and method.